1. Field of the Invention
The present invention is generally directed to an improved storage system for belts of 25 mm insensitive munition (IM) cartridges using existing ammunition cans, and, more particularly, to such a storage system that enhances the IM feature and is simplified.
2. Description of Related Art
Currently, 25 mm linked cartridges are stored in ammunition cans, such as the U.S. Army's PA125 ammunition cans, which hold thirty such linked cartridges arranged in two belts of 15 cartridges each, each belt is held in a retaining plate spaced away from each end of the ammunition can by a thin foam pad, with one retaining plate holding its cartridges vertically within the ammunition can and the other retaining plate holding its cartridges in an opposed, i.e. inverted, position within the ammunition can. There is a separator assembly located between the retaining plates, this separator assembly has a lower set of cavities, each of which rests on the shoulders of one of the two sets of cartridges, so as to fit snuggly, i.e. tightly, hold the middle tapered section of each cartridge therein; whereby, in conjunction with the cavities in the retaining plate, each cartridge is held in place between these two locations. There is also an upper set of cavities within the separator assembly that loosely surrounds the tip of each cartridge. The current retaining plates are generally rectangular, in the form of the internal configuration of standard ammunition cans, and contain a series of cylindrical cavities to support the 25 mm cartridges in a close arrangement. Two sets of linked belts of 25 mm cartridges, when held by the combined retaining plate and the separator assembly forms a composite interlocked assembly which fits snuggly into the ammunition can, thereby minimizing potential movement of the cartridges when the ammunition can is jostled during handling and minimizing the overall size of the ammunition can itself, i.e. for logistic purposes. Obviously, this current system utilizes a number of separate parts, i.e. two foam pads, two retaining plates and one separator assembly—which makes it more complicated, more costly, and more difficult to use on the battlefield.
As stated above, there are a set of thin, ¼ inch, foam backings which separate the base of each retaining plate from the respective top and bottom ends of the ammunition can. The base of each of the 25 mm linked cartridges extends through its respective retaining plate and resting on this ¼ inch foam backing. This arrangement provides that the ¼ inch foam backing will fill any gap between each retaining plate and the respective top or bottom of the ammunition can by which it is positioned; thereby, tending to further minimize any jostling effects.
Newer munitions are designed to minimize any violent (explosive) response when subjected to unintended stimuli during transportation and storage, such munitions are generally known as insensitive munitions or simply as, IM. Generally, such IM type cartridges are provided with means to vent themselves such that when unintentionally subjected to heat or kinetic energy for an accidental fire or the result of enemy action. Such venting avoids pressure build-up if the propellant is ignited and the propellant will then tend to burn rather than explode. In the case of new IM cartridges, such pressure relief can be accomplished by safety devices which will automatically vent any pressure build-up when the temperature approaches the auto-ignition temperature of the propellant within the cartridge. Such venting of the propellant is generally accomplished through the base of the cartridge—considering the location of the propellant adjacent thereto. Unfortunately, any current 25 mm linked cartridges stored as detailed above, i.e. tightly contained in ammunition cans with each cartridge directly resting on a ¼ foam backing pad, will not be able to be vented through its base due to the foam pad.
There is clearly a need in the art for a storage system with a new retaining plate/separator assembly configuration for storing 25 mm linked cartridges in existing ammunition containers that does not impede effective venting from the base of the IM cartridge during an unforeseen heat/kinetic energy event and for a storage system which is simpler and therefore less costly and easier to use by the soldier under battlefield conditions